Device for ladling molten bath of metals



y 1968 TAKAHIKO TAKESHIMA 3,393,837

DEVICE FOR LADLING MOLTEN BATH OF METALS Filed July 19, 1966 2Sheets-Sheet l INVENTOR. TAKAHIKO TAKESHIMA ATTORNEY.

July 23, 1968 TAKAHIKO TAKESHIMA ,3

DEVICE FOR LADLING MOLTEN BATH OF METALS 2 Sheets-Sheet 2 Filed July 19,1966 INVENTOR. TAKAHIKO TAKESHIMA wad ATTORNEY.

United States Patent Oflice 3,393,837 Patented July 23, 1968 ABSTRACT OFTHE DISCLOSURE A device for ladling a molten bath of metals whichconsists of a drive means connected to a power source and disposed onone end of an arm, a fixed circular body on a rotary frame, a circularrotary means fixed with a ladle and being provided on the other end ofthe arm, endless chain means mounted between the fixed circular body andcircular rotary means whereby the ladle is moved with its surfacemaintained in a horizontal position by an ellipsoidal movement of thechain means by virtue of the fixed circular body and circular rotarymeans for the ladling of the molten bath of metals, and means forinclining the ladle mounted on a piston rod of an hydraulic cylinderfixed rotatably through a shaft upon a support base.

The present invention relates to a device for ladling a molten bath ofmetal and in particular refers to a device for feeding molten metalsautomatically from a pan within a furnace into a casting sleeve of a diecasting machine.

Generally, the feeding of molten bath of metals to a die casting machineof the cold chamber system has been made manually for the die casting ofaluminum and like materials. Such automatic feeding machines as havebeen reduced to practical use were mostly of the air pressure type. Inother words, they were of such a type that the pan of the furnace wasclosed airtight, and molten metals were forced to be squeezed out underthe air pressure acting upon the surface of the molten metals. However,they were costly and highly corrosive. Besides, a constant amount offeed bath could not be maintained. Recently, mechanical systems ofdirect ladling have been developed, but they are not adequate to meetthe requirements of the automatic means for feeding the metal bath.

It is noted that in any automatically operating device for feedingmolten metals from a pan into a casting sleeve of a die casting machine,a mechanical or air pressure type, should at least fulfill the followingconditions:

(a) A constant amount of metal bath can be provided at all times and anyadjustment in the amount of bath to be fed may be made with case;

(b) The oxidation of the metal bath, the dripping of the metal bath fromparts of a feeding device and the adhesion of the molten bath onto partsof the device in the course of feeding the molten bath of metals can befully avoided;

(c) Pure molten bath of metals not containing solidified metals or otherimpurities are to be fed;

(d) Supply of molten bath to the pan for molten metals is quite easy;

(e) Simple construction and easy maintenance;

(f) Low manufacturing and installation costs.

The object of this invention is to provide a device for ladling a moltenbath of metals which may fulfill the above-mentioned conditions.

According to the present invention, there is provided a device forladling a molten bath of metals comprising a rotary drive meansconnected to a power source and being provided on one end of an arm, afixed circular body on a rotary frame, a circular rotary means fixedwith a ladle and being provided on the other end of said arm, chains andlike means mounted endlessly between said fixed circular body and saidcircular rotary means, whereby said ladle is moved with its surfacemaintained in horizontal position by an ellipsoidal movement of chainsand the like by means of said fixed circular body and said circularrotary plate so as to ladle the molten bath of metals.

'Furthermore, according to a preferable embodiment of the presentinvention, a worm and a worm-wheel may be used as said rotary drivemeans, and chain-wheels with the same pitch-circle respectively may beused as said fixed circular body and circular rotary means. Further, itis preferable to provide said rotary drive means and the fixed circularbody concentrically.

The device according to the present invention may be also provided witha means for inclining the ladle which is mounted on a piston-rod of aoil pressure cylinder which is mounted rotatably on a support base bymeans of the shaft.

In the above embodiment of the invention, the end of the rotary framemay be connected to any other driving mechanism.

Still more, by the present invention, it has become possible to changethe angle of inclination of the ladle against the surface of moltenmetals when molten bath of metals are ladled.

The device according to the present invention is preferably used incombination with a hopper which is pivotably mounted to locate directlyoverhead of a casting sleeve of a die casting machine and the shakingmovement of the hopper is coupled with the transfer movement of theladle.

In the above embodiment of the present invention, the shaking movementof the hopper may be provided by means of a pressure cylinder.

With the above-described mechanism and operation, the device of thepresent invention can achieve such effects as follows:

1) An amount of molten bath to be fed is determined by an angle ofinclination of the ladle so that a precise amount of bath can be fed. Bychanging the angle of inclination of the ladle, therefore, it is quitepossible to adjust the amount of bath and thereby to obtain anypredesignated amount of bath with much ease.

(2) The ladle is carried to the surface of the molten bath in the stateof inclination as determined previously and is returned to aperpendicular position when the ladle comes immediately above thesurface of the molten bath. Accordingly, there is extremely littlechance of spilling the molten bath from the ladle on the way of feedingthe bath. Since no conduit is employed, as seen in common feedingmachines of the air pressure type, there will be practically nooxidation of the molten bath, dripping of bath from parts of the feedingmeans, and adhesion of bath onto the parts of the feeding means willtake place during the operation.

(3) Since the hopper is transferred only after a complete feeding ofbath has been made in the casting sleeve, there is no mixing ofimpurities produced at the bottom of the ladle and solidified metals onthe surroundings of the ladle in the casting sleeve so that excellentproducts can be obtained.

(4) The heat insulating furnace or the melting furnace can be of theopen-air type with its upper part completely uncovered so that themolten bath or ingots can be supplied very simply.

(5) The device has a very simple construction and the ladle is the onlypart which is required to submerge in the molten bath. Consequentlymaintenance of the device is very simple. In short, the ladle can easilybe replaced with a reserve ladle or by any other adequate ladle in caseit becomes necessary to take out a larger amount of molten bath.

(6) Because of its simple construction, the ladling device according tothe present invention may be installed in any common furnace without anytroubles. Yet its manufacturing and installation costs are held verylow.

The above and other features of the invention and the advantagesderiving therefrom will be evident from the following specification of apreferred embodiment shown by way of non-limiting example with theaccompanying drawings, in which:

FIGURE 1 is a vertical cross sectional view of one embodiment of thedevice according to this invention.

FIGURE 2 shows a cross section of the device on the line llII on FIGURE1.

FIGURE 3 shows a cross section of the device on the line IIIIII onFIGURE 1.

FIGURE 4 shows a cross section of the device showing operative conditionof a ladle according to this invention.

Referring to the drawings, a pan 1 is provided in a heat insulatingfurnace or a melting furnace 2 and in the pan is contained molten bathof metals 3. When the level of the molten bath decreases, additionalmolten metal is supplied in a state of bath for a heat insulatingfurnace while ingot is supplied for a melting furnace.

A ladle 4 is fixed by means of bolts 5 to a ladle fixing plate 6 and hasa construction adapted to be easily replaced.

The ladle fixing plate 6 is fixed to a chain wheel 7 to which is fittedalso a shaft 8 in a rotatable manner. On one end of an arm 9 is fittedthe shaft 8 and on the other end thereof is fitted a drive shaft 10.

There is provided a chain wheel 11 fitted on a rotary frame 12 in such amanner that said chain wheel 11 is disposed concentrically with thedrive shaft 10. The chain wheel 7 and the chain wheel 11 are connectedby means of chains 13 and 14. Between the chains 13 and 14 there areprovided two pieces of turn buckles 15 whereby tension of the chains 13and 14 can be adjusted desirably. Further, diameters of pitch circles ofthe two chain wheels 7 and 11 are made equal.

A worm wheel 16 is provided on the drive shaft 10, said worm wheel beingmeshed with a worm 17 driven by a hydraulic motor 18 provided on therotary frame 12.

On the side walls of the melting furnace or the heat insulating furnace2 is provided a bracket 19 fitted thereon and on said bracket :1 supportbase 20 is fixed by means of bolts 21. On the upper end of the supportbase 20 there is provided a shaft 22 through bearings 23 and said rotaryframe 12 is rotatably mounted on the shaft 22.

Furthermore a hydraulic cylinder 24 is fitted by means of a pin 25 to abracket 26 on the support base 20 so that said hydraulic cylinder canoscillate freely. One end of a piston rod 27 of the hydraulic cylinder24 is fitted at a projection 12A of the rotary frame with a pin 28.

It is further designed that when the ladle 4 is situated at a positionshown by chain line in FIGURES 1 and 2 said ladle comes to a position sothat outlet of the ladle 4 for the molten bath can situate on the lineof extension of axis of the shaft 22.

There is provided a hopper 29 directly above a casting sleeve 30 of thedie casting machine and for this purpose said hopper is fixed at ahopper seat 31 by means of a pin 32 to be capable of oscillating, andsaid hopper seat 31 is attached to a fixed platen 33 of the die castingmachine by bolts 34. Furthermore, a bracket 35 is fitted on said fixedplaten 33 by means of bolts 36, and on this bracket 35 a air cylinder 37is oscillatorily fitted by a pin 38. The projection 29A of the hopper 29is provided at a piston rod 39 of the air cylinder with a pin 40 so asto freely oscillate.

41 is a plunger tip for casting the molten metal 3 in the casting sleeve30 into a metallic mold (not shown). 42 is a plunger rod.

In the drawings, (A) denotes a position of the ladle 4 when lying in themelting furnace or the heat insulating furnace 2; (B) shows a positionwhen the ladle 4 comes directly above the hopper 29; and (C) in FIGURES2 and 3 denotes a position of the ladle 4 when the ladle is tilted fromthe position of (B) by throwing down rotary frame 12 from the positionof (B) and to discharge the molten bath into the hopper 29. (D) inFIGURES 2 and 3 shows a position taken at random by the rotary frame 12when the latter has turned upright after feeding of bath has beenaccomplished.

In the embodiment of this invention, the worm 17 and worm wheel 16 canbe substituted with other common rotary drive means; the chain wheel 11with a fixed circular body; and the chain wheel 7 with a circular"rotary means. In said cases the chains 13 and 14 can be substituted bywire rope and the like.

Operation of the ladling device according to this invention will now bedescribed in detail.

In the first place, it is to be understood that the ladle 4 as shown by(A) in solid line in FIGURE 1 lies below the surface of the metal bath3. However, the rotary frame 12, as shown in FIGURES 2 and 3, is locatedat a position of (D) which makes an angle of 0 with the position of (B)so that the ladle 4 is tilted through the angle 0 and dipped in themetal bath 3, i.e., the ladle will lie in the metal bath 3 in the stateshown by (a) in FIGURE 4.

When the hydraulic motor 18 is revolved by power from a power source notshown, the worm 17 in direct association with the hydraulic motor 18revolves. In meshing with the worm 17 also revolves the worm wheel 13 inthe clockwise direction as shown in FIGURE 1. The arm 9 thereforerevolves in the clockwise direction with the drive shaft 10.Simultaneously chains 13 and 14 in association with the chain wheel 11lying in the concentric circle with the drive shaft 10 revolves thechain wheel 7 associated with the ladle 4 through the fixing late 6 inthe reverse direction of the rotation of the arm 9 through the anglethat the arm 9 has been displaced.

Accordingly the ladle 4 moves maintaining the same posture irrespectiveof the position of the arm 9 wherever it is situated.

When the arm 9 starts to rotate, the ladle 4 rises up from the surfaceof the molten bath while maintaining its inclination at an angle of 0.When the ladle 4 is situated above the surface of the molten bath 3 asshown in FIG- URE 4(b), the surface level of the bath lies at a positionof (M) which is the lowest point on the edge of the ladle 4. In thisstate, the amount of bath to be fed is measured. Therefore by varyingthe inclination angle of the ladle 4 or the angle 0 it is possible toadjust the amount of bath to be fed desirably.

After the measurement has been made, the pressure oil enters the upperpart of the hydraulic cylinder 24 by means of electric signals and thepiston rod 27 is pushed down so that the rotary frame 12 turns incounterclockwise direction around the shaft 22 and stops at aperpendicular position. The ladle 4 too restores a vertical posture froman inclined one, and the surface of the molten bath in the ladle 4 comesto the extent of (H) as shown in FIGURE 4 ,(C), thus preventing thespilling of the molten bath which may otherwise result from theoscillation of the ladle in operation.

In the course of operation, the rotation of the arm 9 is carried out incontinuity. The ladle 4 moves up to the position of (B) as shown bychain lines in FIGURE 1, in other words, it comes to the position justabove the hopper 29, and stops there. Up to that time, the hopper 29remains in the position of (E) in FIGURE 1, and when the ladle 4 comesto the position of (B), simultaneously the pressure air is delivered tothe side of the piston rod 39 of the air cylinder 37. The piston rod 39is pulled to the right side. The hopper 29 turns around the pin 32 andstops at a position of (F) as shown by chain lines. As soon as thehopper 29 comes to the position of (F) the pressure oil enters the lowerpart of the hydraulic cylinder 24. Consequently the piston rod 27 ispushed up and the rotary frame 12 rotates in the clockwise directionaround the shaft 22 as shown in FIGURES 2 and 3 and comes to theposition of (C). The molten bath in the ladle 4, therefore, flows intothe hopper 29 and then into the casting sleeve 30. Thereafter theplunger tip 41 and the plunger rod 42 are advanced to the left side andthe molten bath is cast finally into the mold (not shown).

When flowing of the molten bath into the casting sleeve 30 is finished,the ladle 4 returns to the former position. Thereupon the hopper 29comes back from the position of (F) to that of (E) thereby to preventfrom falling into the casting sleeve 30 the solidified metals andimpurities which have been adhered onto the outside of the ladle 4during the process of casting.

When the ladle 4 arrives at the position of (D) the hydraulic motor 18turns in the reverse direction. The arm 9 then rotates counter-clockwiseand stops in the original positions. Thus one cycle of operation isaccomplished.

I claim:

1. A device for ladling a molten bath of metals comprising: a supportbase, a frame pivotally mounted on said base about a first axis, an armpivotally mounted on said frame about a second axis perpendicular tosaid first axis, a drive means connected to a power source and disposedon one end of said arm, a circular body fixed on said frame concentricwith said second axis, a circular rotary means fixed with a ladle andbeing pivotally mounted on the other end of the arm, endless chain meansmounted between the fixed circular body and the circular rotary means,said drive means being connected to pivot said arm whereby the ladle ismoved with its surface maintained in a horizontal position by anellipsoidal movement of the chain means by means of the fixed circular bbody and the circular rotary means for the ladling of the molten bath ofmetals, in combination with means for inclining the ladle including ahydraulic cylinder and piston rod pivotally mounted on said support baseand pivotally connected to said frame.

References Cited UNITED STATES PATENTS 1,766,574 6/1930 Westin et al. 2l4--1 2,463,811 3/ 1949 Schulze 222166- 3,003,206 10/1961 Peras 222-166FOREIGN PATENTS 1,191,645 4/ 1959 France.

SAMUEL F. COLEMAN, Primary Examiner.

